In the pharmaceutical industry, it is frequently necessary to mix or dissolve a first pharmaceutical constituent with a second pharmaceutical constituent. The constituents may either be a powder and a liquid or two liquids. In many cases, the first of the constituents is a powder ingredient comprising the active medicinal ingredient which is conventionally stored in a vial while the second constituent is a liquid for dissolving or otherwise incorporating the powder ingredient.
In the prior art, it is well known to use a syringe to accomplish the mixing of two pharmaceutical substances. Traditionally, a syringe has been used for accomplishing this step. Thus, in the case of a solid and liquid component, the liquid component is packaged in the syringe with the solid component being packaged in a pharmaceutical vial having a neck closed by a penetrable closure. One then injects the liquid component into the vial through the penetrable closure, mixes the two substances together in the vial to dissolve, dilute or suspend the solid component in the liquid component, and subsequently aspirate the combined components back into the syringe. The above method is disadvantageous in the fact that the user is exposed to the unprotected needle tip and furthermore, loss of a pharmaceutical component can occur through the puncture point. This is particularly dangerous with certain pharmaceutical components such as toxic oncology pharmaceuticals. Still further, the sterility of the needle may be compromised during the process.
A solution to the above is shown in International Application PCT/CA2004/00006, the teachings of which are hereby incorporated by reference. In this patent application, a method of safely mixing two pharmaceutical components utilizing a syringe is shown.
A requirement in the pharmaceutical industry are cartridges which are secured to an injection pen. These cartridges are frequently used where there exists a multidose situation or metered amounts must be injected. A device for mixing two pharmaceutical components for use in an injection pen is required.